Analog-to-digital converters (ADCs) may be used in wireless communication to convert an analog radio frequency (RF) signal into a digital signal. An ADC may include an RF front-end that includes RF filters that reject unwanted frequencies and pass through wanted frequencies (i.e., the “pass band”), and, generally, allow compatibility with one or more communication protocols (e.g., Bluetooth, Bluetooth Low Energy (BLE), Wireless, Near Field Communication (NFC), etc.).
Delta-sigma modulation is a technique for encoding an analog signal (such as analog RF signals) into a digital signal. Unlike quantizers used in conventional ADCs that encode the absolute value of a signal (which introduces quantization error noise into an encoded digital signal), delta-sigma modulation encodes the change in the signal (i.e., its delta). By way of example, a conventional delta-sigma ADC may encode an analog signal using high-frequency delta-sigma modulation and then apply a filter to form a higher resolution, but lower sample-frequency, digital output. Delta-sigma modulation is particularly useful for communication systems because it may achieve higher transmission efficiency by transmitting only the changes in value between consecutive samples, rather than the actual sample values.